I was touched instantly by this song when I first heard it, even though my korean foundation is reallly reallllly weak. =x It just holds something that mysteriously attracts you to it, and keep your heart itching to hear it more. Each time I hear it, I feel empathy with the song. And of course, taeyeon's voice is one of the major factors in this song.
Thanks kyopocanuck for translating this. Now I understand the meaning more.